This proposal provides central support for research in Mental Retardation at UCLA. The Mental Retardation Research Center (MRRC) at UCLA is a multi-funded, interdisciplinary research and teaching program which has the following objectives: Research into problems of mental retardation and related aspects of human development. Research training, at the pre- and postdoctoral levels, of specialists in a variety of disciplines related to our goals. Studies fall into the following categories: Developmental Biology, Neurobiochemistry, Neurophysiology, Behavioral Studies. An emphasis in indicated on applied research. Collaborative relationships are maintained with other UCLA programs in the Neuropsychiatric Institute, and Brain Research Institute, various departments of the School of Medicine, and other schools at UCLA. This application requests funds for administrative and common research support in Core facilities; Administration, New Program Development, Molecular Biology, Neural Cell Culture, Neurohistology, Microcomputers and Media, Statistics and Electronics and Vivarium.